Electrical gas-alarm



(No Model.)

' W. McVAY.

- ELECTRICAL GAS ALARM. No. 358,161. Patented Feb 22, 1887.

WITNESSES: J INVENTOR:

gfff BY MM ATTORNEYS.

N. PETERS'Phom-Lnhcgnphcr. Wnshmgwn. D. C.

UNITED STATES PATENT ()FFICE.

WILLIAM llICVAY, OF QUINCY, ILLINOIS.

ELECTRICAL GAS-ALARM.

SPECIFICATION forming part of Letters Patent No. 358,161, dated February22, 1887.

(No model.)

To all whom it may concern:

Be it known that I, WILLIAM MOVAY, of Quincy, in the county of Adams andState of Illinois, have invented a new and Improved ElectricalGas-Alarm, of which the following is a specification, reference beinghad to the annexed drawings, forming a part thereof, in

which- Figure 1 is a side elevation of agas bracket and burner with myimprovement applied. Fig. 2 is a plan View. Fig. 3 is an enlarged detailsectional view of the thermostat and thermostat-holder. Fig. 4 is anenlarged perspective view of the thermostat-holder. Fig. 5 is anenlarged view of a detail to be described.

Similar letters of reference indicate corresponding parts in thedifferent figures of the drawings.

The object of my invention is to provide a simple and efficient devicefor establishing an electric circuit when the gas-flame is extinguished,and for breaking the. circuit and holding it open while the gas-flame isburning.

My invention consists in the combination, with the burner, of athermostat held near the tip and within reach of the flame andaswitchapplied to the gas-key for breaking the connection with the thermostatwhen the gas is turned off from the burner.

The burner A and gaskeyB are of the usual well-known description. To theburner, near the tip a, is fitted a collar, b, provided with an. arm, a,carrying a split sleeve, (Z, arranged at right angles with the axis ofthe burner. To the split sleeve cl is fitted a brass tube, 6, having theclosed endf provided with a lining, g, of aluminium or other unoXidablemetal. To the tube 0 is fitted a glass tube, h, in which is sealed aplatinum wire, 17, which projects beyond the end of the glass tube andcontacts with the aluminium lining y when the brass tube e is cold. Theglass tube h is secured in the tube 6 by means of a wedge or by cement,or in any other convenient way. Electrical wires j 7c are connected withthe platinum wire 2' and the brass tube e.

To the smaller end of the gas-key B is fitted a plate, Z, projectingequally in opposite direct-ions from the key and arranged parallel withthe -thumb-piece of the key. To the bracket m, in which the key isfitted, is secured an apertured plate, a, surrounding the key andsecured to the bracket. The ends of the plate are turned over towardeach other and bent down upon L-shaped pieces 0 0, of platinum orcopper, with an intervening insulation, 1). The L-shaped pieces 0 0project upward into the path of the plate Z, so that when the key B isturned so as to let the gas into the burner the ends of the plate I willtouch the insulated right-angled pieces 0 0 and establish an electricalconnection between them through the plate Z. The electric circuit isfrom the battery through the wire g to the angled plate 0, and theangled plate 0 is con nected by the wire is with the tube 0, and theplatinum wire i is connected by the wire j with the bell and battery.

When the gas is turned on by turning the key B, the electricalconnection from the bat tery through the bell is established through theangled plates 0, 0, and Z, tube 0, and the platinum wire in the mannerdescribed; but as soon as the gas islighted and the tube 6 is heated,its rate of expansion being greater than that of the tube h, it carriesthe aluminium lining g away from the platinum wire,and thus breaks theelectrical connection; but should the gas be extinguished withoutturning the key B, so as to break the circuit between the angledplatcs00,the cooling down of the tube 6 would bring the aluminiumliningg into contactwith the platinum wire 1, and thus establish theelectric circuit-,which would cause the ringing of the electricalarm-bell and attract attention to the burner.

My improvement is especially adapted for use in hotels andboarding-houses, where people unused to gas are liable to blow out thegas-flame, leaving the gas turned on.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. The combination, in a thermostat for gas burners, oftheexpansion-tubee,providedwith the unoxidable lining g, the platinum wire "5, and theglass tube h, inclosing the platinum wire and secured in the open end ofthe expansion-tube c, substantially as shown and described.

2. Thecombination of the expansion-tube e,

provided with the unoxidable lining g, the the platinum wire'i, of theswitch formed of the IO platinum wire 6, the glass tube h, inclosing theplate Z, carried by the key, the insulated L- platinum wire and securedin the open end of shaped pieces 0 0, supported in the path of theeXpansion-tubee,and the collar b, provided the plate Z, and theelectrical. connections, sub- 5 with the arm candsplitsleeve (Z,substantially stantially as shown and described.

as shown and described. WILLIAM MOVAY.

3. The combination, with the thermostat formed of the expansion-tubee,having the unoxidable lining g, and the glass tube h, coveringVitnesses:

B. W. MONTGOMERY, F. O. PARKER.

